Mature size & growth rate

How big does Stilt Palm (Iriartea deltoidea) get?

Also called Bombona Palm, Walking Palm, Huacrapona.

More about stilt palm

About Stilt Palm

Iriartea deltoidea · also called Bombona Palm, Walking Palm · tropical

A dominant canopy palm of Amazonian and Andean foothill rainforests, recognisable by its extraordinary stilt-like aerial root system that elevates the trunk above the forest floor. Pinnate fronds arch dramatically. Rarely cultivated outside specialist botanical gardens or large tropical estates. Non-toxic to pets.

Mature size: Up to 30 m outdoors in the wild; rarely exceeds 5-6 m in cultivation over many years

Indoor size vs how big it gets in the wild

Stilt Palm is a tree at heart. Indoors a pot and your ceiling keep it to up to 30 m outdoors in the wild, but in the ground it is a different scale of plant entirely (rarely exceeds 5-6 m in cultivation over many years). Indoors and in a pot, expect up to 30 m outdoors in the wild. In the ground with no restriction it is a completely different plant — rarely exceeds 5-6 m in cultivation over many years — which is why the pot, the light and the pruning matter so much for the size you actually end up with.

It gains real height on a trunk or main stem, adding a tier of leaves a year and eventually reaching for the ceiling — this is a plant you grow up, not out.

Growth rate and years to mature

Stilt Palm is a slow grower. Realistically, expect a decade or more — slow growers like this add only a few centimetres a year, so expect 8-15+ years to reach their indoor ceiling. Its feeding profile backs this up: apply a balanced slow-release palm fertiliser in spring and midsummer. this large, vigorous palm in the ground benefits from supplemental organic mulching with leaf mould or composted bark around the stilt root zone.

Want this turned into the right next pot at the right moment? The pot size calculator and the stilt palm repotting guide cover when and how much to size up — pot size is one of the biggest levers on how fast stilt palm grows.

How to keep stilt palm smaller

You are not stuck with the maximum size. For stilt palm specifically, these are the levers, in order of impact:

The decisive tool is the secateurs: stilt palm can be topped (cut the main growing tip) to cap its height and force a bushier, shorter shape.
Keeping it deliberately pot-bound in a snug container slows the whole plant and limits ultimate size.
Prune in spring so it heals fast; remove the tallest leader back to a node to reset the height.
Good news: slow growth means topping it once buys you years before it needs doing again.

The keep-it-smaller method, step by step

Pick the new height. Decide how tall you want stilt palm and find a leaf node or branch point just below that.
Top the main stem. Cut the main growing tip cleanly just above that node in spring; this permanently caps the height and forces side branches.
Keep the pot snug. Avoid jumping to a much bigger pot — a slightly restricted rootball keeps the whole plant smaller.
Maintain the shape. Prune back the tallest new leaders each spring to hold it at the height you chose.

How to grow stilt palm bigger or faster

If you want it to fill the space sooner, push the conditions rather than hoping — for stilt palm the accelerators are:

It already wants the bright light it needs; warmth, a yearly pot-up and spring-summer feed are the accelerators.
Pot up a size every year or two while young; restricted roots are the main thing holding height back.
Feed regularly through the growing season and keep it warm — height comes from sustained good conditions.

Light is almost always the ceiling. The stilt palm light requirements page covers exactly how bright a spot it needs to grow at its potential instead of stalling.

When stilt palm outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for stilt palm:

The top leaves pressing against or bent by the ceiling — the classic "this is now too tall indoors" sign.
It has to be moved away from a light source it has literally outgrown.
Roots filling the largest pot you can reasonably keep indoors — at that point it is top-or-prune or move it outside (if hardy).

If it is the pot rather than the room, it is a repotting job, not a goodbye — see the stilt palm repotting guide. If you want more of this plant instead of a bigger one, the stilt palm propagation guide turns prunings into new plants.

Stilt Palm size — frequently asked questions

How big does stilt palm get?

Stilt Palm reaches up to 30 m outdoors in the wild when grown indoors, and far larger where it grows unrestricted (rarely exceeds 5-6 m in cultivation over many years). It gains real height on a trunk or main stem, adding a tier of leaves a year and eventually reaching for the ceiling — this is a plant you grow up, not out.

Is stilt palm slow or fast growing?

Stilt Palm is a slow grower. Expect a decade or more — slow growers like this add only a few centimetres a year, so expect 8-15+ years to reach their indoor ceiling. Stilt Palm is a tree at heart. Indoors a pot and your ceiling keep it to up to 30 m outdoors in the wild, but in the ground it is a different scale of plant entirely (rarely exceeds 5-6 m in cultivation over many years).

How long does stilt palm take to reach full size?

Roughly a decade or more — slow growers like this add only a few centimetres a year, so expect 8-15+ years to reach their indoor ceiling. Light, pot size and feeding move that timeline more than anything else.

How do I keep stilt palm smaller?

The decisive tool is the secateurs: stilt palm can be topped (cut the main growing tip) to cap its height and force a bushier, shorter shape. Keeping it deliberately pot-bound in a snug container slows the whole plant and limits ultimate size. Prune in spring so it heals fast; remove the tallest leader back to a node to reset the height. Good news: slow growth means topping it once buys you years before it needs doing again.

How can I make stilt palm grow bigger or faster?

It already wants the bright light it needs; warmth, a yearly pot-up and spring-summer feed are the accelerators. Pot up a size every year or two while young; restricted roots are the main thing holding height back. Feed regularly through the growing season and keep it warm — height comes from sustained good conditions.